Double condenser high draft mechanism for roving and spinning frames



June 14, 1949. J. v. WEINBERGER 2,472,929

DOUBLE CONDENSER HIGH DRAFT MECHANISM FOR ROVING AND SPINNING FRAMESFiled Ju ly 16, 1945 I 2 Sheets-Sheet 1 (j B A 5 23 2 7 l/ 13 g E 32 1?-2 r P 1% i C B I A 9 I 1a" I Fe l1 1 g 1 'T" y I "n .m-num] \NVENTORATTOR Patented June 14, 1949 DOUBLE CONDENSER HIGH DRAFT MECH- ANISMFOR. ROVING AND SPINNING FRAMES Jan V. Weinberger, Truro, Nova Scotia,Canada Application July 16, 1945, Serial No. 605,343 In Canada March 23,1945 This invention relates to high-draft mechanism for roving andspinning frames.

The primary objectof the invention is the provision of simple means foreffectively counteracting detrimental eifects of electrical and otherconditions which are encountered in the operation of such high-draftmechanisms and tend to interfere with the production of a smooth rovingor yarn and cause'breakage and stoppages.

In the operation of high-draft roving and spinning frames thedisposition of the component fibres of the sliver during its passagebetween the top and bottom rolls of the various roll units is animportant factor. The ideal fibre arrangement is that presented by acircular sliver since, in this case, all the component fibres are asclose to the central longitudinal line of the sliver as isgeometrically. possible. In a circular sliver the fibre adhesion is suchthat the surface and sub-surface fibres tend to remain with the centralfibres to a much greater extent than in a sliver of any other crosssection. However,

the maintenance of the ideal circular shape of the sliver during itspassage through the various roll units of the high-draft mechanism isnot practically possible.

In ordinary practice the slivers are passed to the entry roll unit ofthe frame through circular openings provided in the usual reciprocatingbar mounted adjacent said unit. The top and bottom rolls of this unitare subjected to spring or weight pressure and tend to flatten thesliver so that it tapers toward its side edges, the fibres at andadjacent said edges being much less thickly and densely bunched ascompared with the fibres at and adjacent the central longitudinal lineof the sliver. When the sliver is passed in this form between the topand bottom rolls of the front or delivery draft roll unit the edgefibres of the sliver which are furthest from the longitudinal centre ofthe sliver exhibit a reduced tendency to remain with the sliver and anincreased tendency to wrap themselves around the delivery rolls. Theseedge fibres of the sliver are also the ones which are most stronglyattracted by the delivery rolls as the result of electric charging ofthe fibres and rolls by static electricity generated by the pressureand/or friction obtaining between the sliver and rolls during thespinning operation. The net result is that, in many instances, thefibres most strongly attracted by the delivery rolls will leave thesliver for the rolls and will causelother fibres to be similarlydiverted from the sliver until finally a point is reached where the massof fibres 2 Claims. (01. 19-130) wrapped around the rolls will break theroving or the yarn and cause other damages or stoppages.

According to the invention described herein the foregoing difiicultiesare eliminated by subjecting each sliver to a fibre-controllingcondensing or reshaping operation before and after its passage throughthe carrying roll unit or units located between the entry roll unit andthe delivery roll unit. In the first condensing or reshaping operationthe sliver which, as previously described, has been flattened during itspassage through the entry roll unit, is reformed into a substantiallycircular sliver. This circular shape of the reformed sliver is notsubstantially altered during passage of the sliver through the carryingroll unit since the pressure exerted on the sliver by the top and bottomrolls of this unit is not strong enough to cause any considerabledeformation. In the second condensing or reshaping operation which takesplace immediately adjacent the rolls of the delivery roll unit thesubstantially circular sliver is reformed into a flattened sliver ofsubstantially oval cross section having its major axis lying in avertical plane perpendicular to the contact line of the delivery rolls.This second condensing or reshaping operation is accomplished by passingthe substantially circular sliver coming from the carrying rolls througha fibre controlling member provided with a relatively deep narrow slotpresenting parallel side wall portions which crowd the contacting fibrestoward the longitudinal centre line of the sliver and thereby reformsthe substantially circular sliver into a substantially oval sliver whosemajor axis is. perpendicular to the contact line of the delivery roll.The fibres which are thus crowded toward the centre line of the sliverby the side walls of said slot are the fibres which, when the sliver isagain flattened during its passage between the delivery rolls, aredisplaced fur thest from the centre line of the sliver and wouldordinarily tend to leave the sliver and adhere to said rolls. I havefound, however, that the aforesaid crowding of these fibres toward thecentre line of the sliver as the sliver enters the nip of the deliveryrolls has the effect of decreasing the electrical attraction of thesefibres by said rolls and otherwise counteracting the tendency of thesefibres to be diverted from the sliver during its passage through thecarrying roll unit. The fibres at the top and bottom of the oval sliverproduced by the fibre crowding action of the aforesaid slot walls areuncontrolled during the passage of the sliver through the slot units Band C.

"3 but when the sliver is flattened during its passage between thedelivery rolls, these flbres are located in the central portion of thesilver and are controlled by the rolls so that they exhibit no tendencyto leave the sliver.

The extent to which the component fibres of the sliver are spread apartand diverted from the sliver during the drawing process is largelydependent on the static electricity with which the sliver and drawingrolls are charged and this, in turn, is dependent on'the friction andpressure obtaining between the fibres and the rolls. This friction andthe resulting charging of the fibres and rolls with static electricityincreases as the difference between the surface speeds of the entry anddelivery rolls is increased to provide more draft or elongation of thesliver. The practical draft limit is reached at the point where thesliver tends to disintegrate under the influence of the disintegratingaction of the static electricity. mechanism equipped with my inventionthe detrimental efiects of static electricity are counterated andnullified so that it is possible to safely exceed to a very substantialextent what has previously been considered the practical limit of thedraft and to thereby obtain a far greater elongation of the sliver thanhas heretofore been obtained with the use of a single condenser.

In the further description of this-invention reference will be had tothe preferred mechanical embodiment shown in the accompanying drawing,-

in which Fig. 1 is a fragmentary top plan view of the drawing part of aspinning frame assembly equipped with my invention.

Fig. 2 is a cross sectional view taken substantially along the sectionline 2-2 of Fig. 1.

Fig. 3 is a perspective view in which certain parts are shown insection.

Fig. 4 is a perspective view of one of the sliver condensing orreshaping members by means of which the flattened sliver coming from thedelivery roll unit is reformed into a substantially circular sliver; and

Fig. 5 is a perspective view of one of the sliver reshaping orcondensing elements by means of which the substantially circular slivercoming from the carrying roll unit is reformed into a flattened sliverhaving its upper cross sectional axis lying in a vertical plane.

In these drawings my invention is shown applied to a conventionalhigh-draft mechanism for roving and spinning frames comprising an entryroll unit A, a carrying roll unit B, a delivery a roll unit C and theusual reciprocating bar D provided with openings E through which theslivers or rovings F are directed between the top and bottom rolls 5 and6 of the aforesaid roll units.

During its passage through the top and bottom entry rolls of unit A eachsliver is flattened as indicated at F and is transformed into a sliverof substantially oval cross section having its major axis lying in theplane of or parallel with the contact line of the top and bottom rollsor The oval shape of the sliver is not materially altered during passageof the sliver between the top and bottom rolls of unit B since thepressure of these rolls on the sliver is not strong enough to cause anyconsiderable deformation. sliver passes between the top and bottomdelivery rolls of unit C in the substantially flattened oval conditionimparted thereto by the entry rolls.

However, in the case of high-draft in various difllculties includingdisintegration of the sliver under the influence of static electricity.

According to my invention a series of silver condensing or reshapingmembers 8 are arranged between the rolls of units A and B and a secondseries of sliver condensing or reshaping members 9 are arranged betweenthe rolls of units B and C.

As each sliver passes through one of the condensing or reshaping members8 it is reformed into a circular sliver as indicated at F". In thisconnection it will be noted that each member 8 comprises a porcelain orsimilar element provided with a substantially circular eye "throughwhich the sliver travels during the spinning process. Each member 8 isalso provided with a flaring vertical slot l l which serves as anentrance opening through which the sliver is introduced into the eye Inat commencement of the spinning process. The members 8 aresecured byscrew threaded shanks l2 or other suitable means to a commonhorizontally extending supporting bar cause any considerabledeformation.

As each sliver travels from the carrying rolls of unit B to the deliveryrolls of unit C it passes through one of the condensing or reshapingmembers 9 and is reformed into a flattened sliver F of substantiallyoval cross section having its major axis perpendicular to the contactline of the delivery rolls. In this connection it will be noted thateach sliver condensing or reshaping member 9 comprises a porcelain blockor the like which is positioned immediately adjacent the delivery rolls5 and 6 of unit C and is provided with a vertical slot l8 extendinghorizontally therethrough in a direction perpendicular to the rolls,said slot being bounded by side walls l9 and bottom wall 20 and beingopen at the top and ends. The side walls of the slot l8 are curved orflared so that they are closely spaced and substantially parallel at theexit end of the slot and are widely spaced at the entrance end. Duringits passage through this slot the fibres of the substantially circularsliver are gradually com- Consequently, in ordinary practice, the

is es fr the narrow end of the lot in the form of a fie ed andsubstantially oval silver having its principal axis vertical to thecontact line of the delivery rolls between which the sliver is thenpassed. As previously described this reformation of the sliverimmediately prior to its passage between the delivery rolls gives afibre controlling effect which'counteracts the disintegration of thesliver and the other difliculties which are encountered when theflattened sliver is passed between the delivery rolls with its majoraxis co-planar or parallel with the line of contact between said rolls.Y

The sliver condensing or reshaping elements 8 are fastened by screws 22or otherwise to a common supporting bar 23 carried by upward extensionslSc of the horizontal supporting member l5. Member If is also providedwith upward extensions 24 which are secured to reciprocating bar D. Itwill thus be seen that the reshapin or condensing members 8 and 9 aremounted to move with the reciprocating bar D.

The initial reshaping operation by which the flattened sliver comingfrom the entry roll unit is reformed into a sliver of substantiallycircular cross section before passing through the carrying roll unit isan important feature of the invention. This feature of the inventionprovides for a more gradual transition of the sliver, by compression ofthe component fibres, from the flattened condition shown at F to theflattened condition shown at F If the sliver, after being flattened tothe condition shown at F, is passed through the reshaping member 9without the intermediate reforming of the sliver into a sliver ofsubstantially circular cross section, the resulting sliver formation isnot as satisfactory as that obtained when the sliver is reformed into asubstantially circular silver before being passed through the carryingrolls of unit B.

Having thus described the nature of my invention, and a preferredmechanical embodiment thereof, it will be understood that variousmodifications may be resorted to within the scope and spirit of theinvention as defined by the appended claims.

I claim:

1. A high-draft roving mechanism comprising a roving frame equipped withan entry roll unit, a carrying roll unit and a delivery roll unitthrough which the slivers are successively passed, sliver condensing orreshaping members through which the slivers are passed from the entryroll unit to the carrying roll unit and by means of which the sliversare reformed into slivers of substantially circular cross section and asecond series of sliver condensing or reshaping members through whichthe slivers are passed from the carrying roll unit to the delivery rollunit and by means of which the slivers are transformed into flattenedslivers each having its major cross sectional axis lying in a verticalplane.

2. A high-draft roving mechanism comprising a roving frame equipped withan entry roll unit,

a carrying roll unit and a delivery roll unit through which a pluralityof slivers are successively passed, a series of sliver-reformingcondensers arranged between the entry roll unit and the carrying rollunit so that each sliver passes through a separate one of saidcondensers in travelling from the entry roll unit to the carrying rollunit, each of said condensers presenting a substantially circularsliver-receiving eye by means of which the sliver passing therethroughis transformed into a sliver of substantially clrcular cross section anda plurality of sliver-reforming condensers arranged between the carryingroll unit and the delivery roll unit and close to the draft or deliveryrolls of the last mentioned unit, said last mentioned condensers beingarranged so that a separate sliver passes through each of said lastmentioned condensers in passing from the carrying roll unit to thedelivery roll unit and each of said last mentioned condensers presentinga vertical sliver-receiving slot having its side walls shaped so thatthe sliver passing therethrough is transformed into a flattened sliverhaving its major cross sectional axis lying in a vertical plane.

JAN V. WEINBERGER.

REFERENCES CITED The following referemces are of record in the file ofthis patent:

UNITED STATES PATENTS Number

